The "Bernice D" is a gasoline powered fishing boat typical of many used on the Great Lakes in the first half of the 20th century. Fishing for lake trout, white fish and other species was a major industry from the early 19th century until the sea lamprey, an ocean predator which entered the lakes in ships ballast water, decimated the fish population and wiped out commercial fishing on the lakes in the 1940's-1950's.